Extramarital

Extramarital sex occurs when a married person engages in sexual activity with someone other than his or her spouse. From a different perspective, it also applies to a single person having sex with a married person.

Where extramarital sexual relations breach a sexual norm, it may also be referred to as adultery (sexual acts between a married person and a person other than the spouse), fornication (sexual acts between unmarried people), philandery, or infidelity. These terms may also carry moral or religious consequences in civil or religious law.

Engagement in extramarital sex has been associated with individuals who have a higher libido (sex drive) than their partner.

American researcher Alfred Kinsey found in his 1950-era studies that 50% of American males and 26% of females had extramarital sex. Depending on studies, it was estimated that 26–50% of men and 21–38% of women, or 22.7% of men and 11.6% of women had extramarital sex. Other authors say that between 20% and 25% of Americans had sex with someone other than their spouse.Durex's Global Sex Survey has found that 44% of adults worldwide have had one-night extramarital sex and 22% have had an affair. According to a 2004 United States survey, 16% of married partners have had extramarital sex, nearly twice as many men as women, while an additional 30% have fantasized about extramarital sex. There were also studies that have shown rates of extramarital sex as low as 2.5%.

Extramarital sex is considered to be immoral by Christianity, who base this primarily on passages like 1 Corinthians 6:9-10:

It is listed as a sin here and in other passages (along with idolatry, theft, greed, lying, and sexual perversion. While the next verse from the above passage is quick to point out that although some Christians used to practise those sins—that they have since been "justified in the name of the Lord Jesus Christ" and are thus forgiven their sins—extramarital sex has historically been considered to be one of the more serious and damaging sins, possibly because of passages like 1 Corinthians 6:18 that speak of it as sinning against one's own body.

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